Car Tachometer with 555 IC

Pulses are received by the timer from the distributor points. When the timer output is high, Meter M receives a calibrated current through R6. The meter don’t receives any current for that part of the duty cycle after time-out. A visible indication of engine speed is provided by integration of the variable duty cycle by the meter movement. Here’s the circuit diagram:

567 IC Pulse Generator With 25% Active FactorUnique applications of 567 tone/frequency decoder IC? Here is one of them: pulse generator with 25% duty cycle (active factor). This signal generator produce square wave pulse, and you use it as clock source or other purpose. Here is the … Continue reading →...

555 IC for Square Wave Tone Burst GeneratorSquare wave tone bursts is provided by depressing the pushbutton. It’s duration depends on the duration for which the voltage at Pin 4 exceeds a threshold. Astable action of the timer IC is caused by components R1, R2, and C1. … Continue reading →...

Oscilloscope-Triggered Sweep using 555 ICWe can use the 555 timer to hold the cost down of adding a triggered sweep to an economy oscilloscope. The timer is triggered by the circuit’s input op amp, adjusting its flip-flop and cutting off its discharge transistor so … Continue reading →...

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555 Oscillator With 50% Duty CycleTo generate 50% active factor (duty cycle) using 555 IC, we can use two diodes to separate the charging and the discharging path. With no diodes, we can also generate 50% duty cycle using 555 IC by configuring the circuit … Continue reading →...